Machine for tightening the insulation applied on winding bars of electric machines and apparatus



' 1,633,741 June 28, 1927. I E. HAEFELY v momma FOR TIGHTENLNG THEINSULATION APPLIED 0N WINDING BARS OF ELECTRIC MACHINES AND APPARATUSFiled March 1923 Patented June 28, 1927.

ENETED STATES PATENT OFFICE..,.

EMIL HAEFELY, OF BASEL, SWITZERLAND.

MACHINE FOR TIGHTENING'THE INSULATION APPLIED ON WINDING BARS OFELECTRIC MACHINESAND APPARATUS.

Application file'd March 8, I923, Serial No.

This invention relates to an improved machine for tighteniin andsmoothing layers of insulating material wound on spools and bars ofelectric machines and apparatus. It is well known that winding'bars ofrectangular cross-section are covered with an insulating material woundon by means of a winding machine. In spite of tight drawing of theinsulating material in such a machine, it is not always possible toavoid creases be ing formed and the loosening of the covering layers. Ithas therefore been suggested that the tightening and smoothing of theinsulating layers of material wound on spool bars of electric machinesand appara tus may be effected by means of smoothing bands running inopposite directions, which in conjunction with simultaneous heating ofthe article to be covered, bring about by their movement a tightening ofthe insulating material.

The invention is based on this well-known arrangement, but it assumesthat the tightening of the insulating material can only be doneperfectly if the latter can be moved round the sides of the insulatedwinding bar, that is to say, that the movement of the insulatingmaterials is not impeded in any way by counter supports or the like.Moreover, it will not do in the case of long winding bars, to usecorrespondingly wide smoothing bands, as such bands cannot have the sametightening effect all over their width and these requirements have beentaken into account by the fact that the smoothing bands are divided upin their width into narrow single bands, running as closely as possibleside by side, and these are conducted over the broad side of any onewinding bar, leaving the narrow sides of the same free in such a waythat they effect a continuous movement of the insulating material aroundthe winding bar. i

It is advantageous for the smoothing bands to pass over a hot plate,which is arranged behind them and forms a. rectilinear guide for them.

The drawing shows a way of carrying the invention into effect:

Figure 1 is a vertical section through the tightening and smoothingdevice proper;

Figures 2 and 3 show a front and side elevation of the entirearrangement, together with the driving mechanism.

On the upper part of the frame a, are two 623,814, and in SwitzerlandMarch 9, 1922. I

vmovable one 6 serves as a bearing for the with the endless transportrollers e, e,

The

smoothing band running over same.

.smoothing bands of each row he as close together alongside of eachother as the transport rollers permit, and form in their working portionan even smoothing surface right across their entire width.

Between the two rows of smoothing bands, the piece of Work to be woundround in this case, say the notch bar 40 of'an electric machine windingspool, is inserted and placed in the notched part b of the bearers ofthe pair 6 The smoothing bands of both rows run with their working partsover the heatmg plates 9 (heated, for instance, electrically), which arecarried between the respective bearers by holders h.

The smoothing bands of the two rows are driven in such a way thatthesmoothing bands of one row in their working part run in the oppositedirection to the working part of the smoothing bands of the other row.For this purpose, chain wheels 2' are attached to the shafts of thetransport rollers 0 and e, on which an endless driving chain 70 runs,which is conducted round an intermediate tightening roller m. Thedriving chain is is propelledby an electric motor n.

The lower row of smoothing bands together with the corresponding heatingplate serving as a guide for the smoothing bands, is pressed withadjustable pressure against the work piece a, which finds a support inthelower row of smoothing bands or in the corresponding heating plateserving as a guide for the same. For this purpose the pair of bearers bare fitted to the frame a by means of the slides 0 in a verticallyadjustable manner, the said slides being movable upwardly by means ofthe lever 39, which is loaded by a weight. A cam shaft Q the camof whichcan be turned below the lever 12 allows the lowering ofthe slides 0together with the pair of bearers b and the lower smoothing band row tounload the work piece at for the removal thereof.

The working of the device can be readily understood. The rows of drivensmoothing bands move in their working parts in opposite directions oneach side of the inserted Work piece a; and thus smooth the insulatingmaterial around the same so that the parts thereof are drawn tight inone direction on the underside and the insulation parts are drawn tightin the opposite direction on the upper side, so that in their action thetwo rows of smoothing bands supplement each other. The heat which theyat the-same time convey from the heating plates to the layers ofinsulating material of the work piece facilitates or favours thissmoothing and tightenin What I claim is A machine for tightening theinsulation applied on Winding bars of rectangular cross-section forelectric machines and apparatus, comprising two row of movable narrowsmoothing bands, a movable carrier for one of said rows of smoothingbands, a driving device to cause the smoothing bands of the two rows torun in opposite directions, said two rows of bands constituting a freespace between them throughout their operative length, and means toreceive an insulated Winding bar within said space in such a position asto present their wide sides only to said smoothing bands While theirnarrow sides remain free, so that the smoothing bands when moving overthe said wide sides of the winding bar produce a continuous smoothingand tightening of the insulating material round about the same.

In witness whereof I have hereunto signed my name this 16th day ofFebruary 1923.

- EMIL I-IAEFELY.

